Coastal Aquaculture and Mariculture (2+1)

Unit 1 - Shore based aquaculture and mariculture

1.2.5. Sea cucumbers

• The most commonly cultured sea cucumbers are the temperate Japanese sea cucumber (Apostichopus japonicus) and the tropical sandfish (Holothuria scabra).
• Aquaculture production of H. scabra is low and is generally still in the experimental phase.
• However, there is substantial production of A. japonicus from both land-based aquaculture and mariculture in China and Japan. Estimated Chinese production of A. japonicus in 2003 is 6 335 tonnes, of which 5 865 tonnes (93 percent) were from cultured production and only 470 tonnes from the wild fishery.
• Farming of A. japonicus is well established in northern China. Most production is from earthen ponds, but there is also some mariculture using sea cages on the substrate or suspended below rafts.
• The sea cucumbers are fed Sargassum and other macro-algae. In contrast, sea cucumber farming in southern China is only beginning and is likely to utilize the species Holothuria scabra, H. nobilis and H. fuscogilva.
• In Japan juveniles of A. japonicus are stocked in coastal waters to replenish local stocks or to develop new harvest fisheries.

 

• In Indonesia, H. scabra is farmed in cages of 20x20 m or 40x20 m in shallow (0.75–1.0 m deep) coastal areas or in coastal fish ponds. Organic material (such as rice bran and animal dust) is added at 0.2–0.5 kg per m2 every two weeks. Holothuria scabra grow relatively slowly and it takes approximately six months to reach the preferred harvest weight of 200–250 g. Seed stock supply is mostly from the wild, although there is some hatchery production of juveniles.

Seed production technology

Seed production technology for several sea cucumber species is well established in China. Since the 1980s approximately 6–8 billion juvenile A. japonicus have been produced. In 1994, 2.6 million seeds were produced in Japan. Techniques for production of H. scabra have been developed in India, Indonesia, the Solomon Islands, New Caledonia, Vietnam and Australia. Constraints to hatchery production of H. scabra in Indonesia include accessing suitable brood stock and low rates of survival to juvenile . Sea cucumbers require large areas for nursery and grow-out phases because growth rapidly becomes limited as density increases. For this reason, there has been considerable focus on their use for sea ranching.

Sea cucumber